CRA disabled EFILE and NETFILE functions on Monday last week after the discovery of Heartbleed, which can exploit a weakness in encryption software meant to protect transmitted information from being intercepted and read.

Usually individual tax returns are due April 30, but because of the service interruption, CRA will not charge interest or penalties on 2013 filings submitted by May 5.

The feds shut down several other unspecified websites last week, but the Treasury Board announced that all were brought back online on Sunday.